It is aimed to investigate whether red cell distribution with (RDW) to lymphocyte ratio (RLR) can predict early comorbidity among cardiac surgery patients.

There are important developments in the field of cardiac surgery due to advances in medical treatments, surgical techniques, intraoperative anesthesia management, and postoperative intensive care. On the other hand, the proportion of high-risk patients has increased due to the increasing number of elderly patients with comorbidities presenting for cardiac surgery. It is important to analyze outcomes such as postoperative morbidity and mortality, due to concerns about the quality of life of patients after cardiac operations, the recommendations of current ERAS protocols, and the shortening of intensive care unit length of stay. Complications such as cardiac, pulmonary, renal, and neurological disorders, infections such as pneumonia or sepsis, and prolonged stay in the intensive care unit and hospital are indicators of not only the quality of care but also the quality of life after cardiac surgery. Therefore, it is important to determine the perioperative risk factors that cause postoperative morbidity. Various outcome prediction models are used for cardiac surgery, such as the Cardiac Anesthesia Risk Assessment score, Tuman score, Tu score, and the European System for Cardiac Operative Risk Assessment score, which uses preoperative factors to predict the postoperative outcomes. It is known that intraoperative factors such as CPB duration, aortic cross-clamp time, surgical technique, and serum lactate levels are associated with postoperative morbidity. Recent studies suggest that inflammatory and immune imbalance may play an important role in postoperative complications. Studies point to new parameters derived from preoperative complete blood count as potential biomarkers of inflammation and oxidative stress. Many markers such as Neutrophil/Lymphocyte ratio, Mean platelet volume (MPV) or RDW alone have been studied in cardiac surgery. The ratio of red cell distribution width (RDW) to lymphocyte (L) has been popular in recent years as an indicator of poor prognosis, especially in oncological patients. However, this marker has not yet been evaluated in terms of morbidity or mortality in cardiac surgery patients.

The main purpose of this study; To investigate the RDW/L ratio as an early morbidity marker in cardiac surgery patients.

Inclusion Criteria:

• Adult patients undergoing open-heart surgery with cardiopulmonary bypass

Exclusion Criteria:

• Re-operations
• Emergency operations
• Patients with preoperative renal failure
• Patients with preoperative hematological problems
• Patients with preoperative infection
• Patients with preoperative immunological disease
• Patients using preoperative steroids

Patients who have undergone open-heart surgery with cardiopulmonary bypass in our hospital within the last year will be evaluated retrospectively.